docs: def status_set(workload_state, message):
      """Set the workload state with a message
  
      Use status-set to set the workload state with a message which is visible
      to the user via juju status. If the status-set command is not found then
      assume this is juju < 1.23 and juju-log the message unstead.
  
      workload_state -- valid juju workload state.
      message        -- status update message
      """
      valid_states = ['maintenance', 'blocked', 'waiting', 'active']
      if workload_state not in valid_states:
          raise ValueError(
              '{!r} is not a valid workload state'.format(workload_state)
          )
      cmd = ['status-set', workload_state, message]
      try:
          ret = subprocess.call(cmd)
          if ret == 0:
              return
      except OSError as e:
          if e.errno != errno.ENOENT:
              raise
      log_message = 'status-set failed: {} {}'.format(workload_state,
                                                      message)
      log(log_message, level='INFO')